12/13/2011

Yesterday the Supreme Court agreed hear Arizona v. United States, the challenge to the controversial Arizona law regarding illegal aliens. (From SCOTUSBlog, details here, analysis from Lyle Denniston here, discussion in the Community here). Most observers see this as an immigration case, but it has potentially broader significance for preemption of state laws under Article VI.

At Opinio Juris, leading immigration and foreign affairs law scholar Peter Spiro observes:

This will be a big decision at the intersection of immigration and federalism, probably the biggest since [the Court's] 1942 decision in Hines v. Davidowitz. It could also have important implications for foreign relations federalism. My guess is that the Court is going to split the difference here. I think it’ll uphold a key provision requiring law enforcement to undertake immigration status determinations, but it will nullify another which in effect makes undocumented status a crime under state law (it isn’t under federal). But it will raise the overall bar for preemption, moving away from Hines’ hair-trigger standard, even in such sensitive areas as immigration an[d] foreign affairs.

If Professor Spiro’s prediction is right, my sense is that the result will move preemption law a bit back toward where, originally speaking, it should be.

Preemption should be fairly straightforward. State laws that conflict (explicitly or implicitly) with constitutional federal laws are preempted. State laws that don’t conflict with constitutional federal laws are not. If Congress wants to preempt state law, it’s easy enough to write that result into the applicable statute. But in the past the Court has indulged in a confusing array of textually and historically unsupported speculations about federal structure and congressional purposes that go well beyond anything that's in either Article VI or in the relevant statute. In foreign affairs, in particular, the Court has sometimes found a presumption in favor of preemption, either because foreign affairs is a uniquely national area as a matter of constitutional structure or because it assumes Congress would want broad preemption – again due to the nation-wide implications – even if Congress hasn’t said so directly. None of this seems necessary or appropriate. Congress is perfectly capable of protecting itself from the states.